If like me you have an old PS/2 type KVM, you will have the same problem connecting "new" hardware to it. I only need a keyboard as not every running server needs a GUI - so that seemed "sufficient" to make sense. But unfortunately it had no effect. KVM sees the keyboard but no signal is sent to the device. The old triple mouse/keyboard connector plugs right in, so it's definitely a bug in the device itself. Luckily, it's priced right for what it takes to ignore sending it back. Just a note for others - this may not work for you and just go with the more expensive option instead.
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